Question

1. Describe in detail the embryonic developmental program; be sure to include the sex determination process in humans. Define homologous and analogous and explain these terms’ significance in relation to male/female genital development.

Answer 1

Embryonic developmental program is the earliest stage in the development of embryo which leads to formationof fetus. First of the stage starts off by the fertilization of the eggs in female by the male cells called 'sperms'. Fertilization is the process of fusion of male gamete tofemale gamete.After fertilisation the egg (ovum) becomes a zygote.The zygote then undergoes several mitotic divisions.This is called Cleavage. This gives rise to multicellular embryo which further grows into a fetus.There are 23 pais of chromosomes in human body out of whih the last one pair is the sex chromosome.A female has both X and X in their sex chromosome where are maleshave X and Y in the sex chromosome pair.The sex determination is done by the presence or absence of Y protein in the RNA gene of male gamete. Homologous are parts which look similarbut differ in function while, Anologous are parts which look different but have same function.